JP2005314940A - Chemical grouting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chemical grouting device capable of swelling a bag body securely, forming a clearance for grouting chemicals for improving the ground between bag bodies securely, and reinforcing the ground securely. <P>SOLUTION: This chemical grouting device is constituted in such a way that it is composed of a grouting external pipe 1 provided with packers 4 which are a plurality of bag bodies having water permeability and swelling to become larger than digged hole diameter at an interval in the axial direction and a grouting internal pipe insertable into the grouting external pipe 1, solidifying material is filled into the bag bodies from the grouting internal pipe to swell the bag bodies, consolidate peripheral ground, and form the packers 4, and solidifying material is grouted between the packers 4 to solidify a predetermined region by grouting. A grouting port 5 provided in the grouting external pipe 1 in the packer 4 is covered with a sleeve 6 with a collar 6a which becomes an openable and closable check valve opened by grouting pressure. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a chemical solution injection device for ground reinforcement.

  As a ground strengthening method to stabilize the unstable ground that has fluidity due to the surrounding ground in the deep underground and the presence of groundwater, there is a method of injecting a solidified material into the ground of a predetermined target area ( For example, see Patent Document 1).

  This includes a step of injecting a caking material into the ground in a predetermined area over the entire ground, and an inflatable bag to be attached to the hollow tube and its tip in or through the predetermined area. A plurality of anchor bodies composed of a body, filling the bag body with a solidified material through the hollow tube, inflating the bag body and consolidating and strengthening the surrounding ground to a predetermined region It will strengthen the ground.

The bag body is also attached to the middle part of the hollow tube as occasion demands, and if necessary, the expansion of the bag body is formed in the gap around the hollow tube in the hole into which the bag body is inserted. The consolidated material is filled before or after expansion. The filling of the consolidated material is performed on the target ground through a plurality of discharge holes formed in the peripheral surface of the hollow tube from the inner tube inserted into the hollow tube.
Japanese Patent No. 2509005

  The method described in Patent Document 1 is for injecting a caking material into a bag body from a discharge port formed in a hollow tube to swell the bag body, but the bag body is filled with the caking material. However, if the injection is continued, the caking material may flow back from the bag body to the hollow tube, which not only prevents the bag body from expanding reliably but also forms a gap between the bag bodies. There is a possibility that the ground cannot be improved by injecting a caking material into the ground between the bags.

  The object of the present invention is to eliminate the inconveniences of the conventional examples, to surely inflate the bag body, and to reliably form a gap for injecting a chemical solution for improving the ground between the bag bodies. Therefore, an object of the present invention is to provide a chemical liquid injector capable of surely strengthening the ground.

  In order to eliminate the inconvenience of the conventional example, the present invention according to claim 1 includes an injection outer tube including a plurality of water-permeable bags that swell larger than the diameter of the hole at intervals in the axial direction. It consists of an injection inner tube that can be inserted into the outer injection tube, filled with a solidified material from this injection inner tube into the bag body, inflates the bag body, consolidates the surrounding ground, forms a packer, and solidifies between this packer In a chemical injection device for injecting and solidifying a predetermined region by injecting a material, covering an injection port provided in an outer injection tube in the packer with a hooked sleeve serving as an openable / closable check valve opened by injection pressure It is a summary.

  According to the first aspect of the present invention, since the check valve is provided at the inlet provided in the outer injection tube, the check valve is closed when the bag is filled with the packer grout material. It is possible to prevent the packer grout material from flowing back in the direction, so that the packer can be reliably bulged. Thereby, the space | gap for chemical | medical solution injection | pouring between packers can be formed reliably, and the ground improvement by chemical | medical solution injection | pouring can be performed reliably.

  The check valve is formed of a sleeve with a hook, so that the gap between the pair of hooks is opened by the discharge pressure of the packer grout material, and it is closed when the bag is full and the discharge pressure disappears. Open and close reliably with a simple structure.

  Since the chemical injection device of the present invention is provided with a check valve with a hooked sleeve at the injection port provided in the injection outer tube, the check valve is formed by opening and closing a pair of bags when the bag is filled with packer grout material Is closed, and the packer grout material can be prevented from flowing back from the bag body toward the injection outer tube, and the bag body can be reliably expanded. Thereby, the space | gap for chemical | medical solution injection | pouring between packers can be formed reliably, and the ground improvement by chemical | medical solution injection | pouring can be performed reliably.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded front view showing an embodiment of a chemical liquid injection device of the present invention. The chemical liquid injection device of the present invention includes an injection outer tube 1 and an injection inner tube 2 slidably inserted into the injection outer tube 1. In the injection outer tube 1, a plurality of packers 4 are mounted on the outer surface portion at intervals in the axial direction of the hollow tube 3, and the injection ports (in FIG. 1) are arranged between adjacent packers 4 and in the packers 4, respectively. Are not shown).

  The injection port 5 formed in the packer 4 has, for example, a horizontal slit shape as shown in FIG. 3 or a hole shape drilled in a radial direction such as 90 degrees, and covers the injection port 5. A sleeve 6 with a flange 6 a is attached to the injection outer tube 1.

  This sleeve 6 is made of a flexible material such as rubber, and a check valve that opens when the heel 6a is discharged by the discharge pressure of the packer grout material discharged outside the injection outer tube 1 and closes when the discharge pressure is exhausted. A ring-shaped sleeve body is provided with a pair of ridges 6a projecting from one end of the ring-shaped sleeve body, the ridges 6a face each other, and a space between the ridges 6a is formed at the discharge port of the packer grout material.

  The packer 4 is, for example, a plurality of (two in the example shown in FIG. 2) bag bodies that are formed to have a length of 1 m and are tightened at least in the middle, and are configured so that the inlets 5 are opened in the upper and lower sections, respectively. . In addition, a 1-m bag may be used as it is as a series. In addition, the material is water-permeable so that a part of the solidified material can pass therethrough, and woven fabric, unemployed cloth, net, etc. are used as the water-permeable bag body, and it expands larger than the diameter of the hole to be described later. It is formed in such a diameter.

  The injection port formed between the packers 4 is provided with a circular shape in a radial arrangement, for example, at 2 to 4 locations in the circumferential direction of the hollow tube 3 forming the outer injection tube 1, and the outside of this injection port is shown in FIG. As shown, it is covered with a slit disk 7 which is a flexible sleeve made of rubber or the like. The slit disk 7 is provided with a longitudinal slit 7a serving as a discharge port for the chemical liquid. For example, when the interval between the packers 4 is 1 m, two slit disks 7 are attached by positioning 300 mm vertically. The length of the vertical slit 7a is about 100 to 200 mm.

  As shown in FIG. 1, the injection inner tube 2 has a discharge port 9, and the packer portion 10 is in close contact with the inner surface of the hollow tube 3 of the injection outer tube 1 with the front and rear sides thereof as a packer portion 10. There are three types such as a triple packer type shown in FIG. 1 (b) and a double triple packer type shown in FIGS. 1 (c) and 1 (d).

  Next, a method for strengthening the ground using the chemical solution injector will be described. First, the target ground is drilled into the casing to a predetermined depth, the insertion hole 11 is drilled, the injection outer tube 1 is inserted into the casing of the insertion hole 11, and then only the casing is pulled out. Insert the injection tube 2 into the tube.

  In order to prevent the packer 4 from being caught by the hole wall of the insertion hole 11 or the peripheral wall of the casing when the injection outer tube 1 is inserted, the packer 4 is formed by a semi-circular fixing band made of a synthetic resin such as plastic. It is fixed to. The fixing band is not limited to the above-described shape as long as it can be easily removed by the injection pressure of the packer grout material as will be described later.

  The discharge port 9 formed in the injection inner tube 2 is matched with the position of the packer 4 of the injection outer tube 1, and the packer grout material is discharged from the injection inner tube 2. As the packer grout material, for example, a low alkali type injection material having a low viscosity at the beginning of injection and a viscosity increasing rapidly after about 5 minutes is used.

  The packer grout material is discharged from the discharge port 9 into the hollow tube 3 of the injection outer tube 1 and is injected into the packer 4 from the injection port 5 formed in the hollow tube 3. At this time, as shown in FIG. 3 (b), the packer grout material pushes and opens the ridge 6 a facing each other in the contact state of the sleeve 6 with its discharge pressure, and discharges it into the packer 4. When the inside of the packer 4 is filled with the packer grout material and the packer 4 swells, the discharge pressure is lost, so that the flange 6a is closed and functions as a check valve.

  Further, although the packer 4 is fixed to the hollow tube 3 with a fixed band, it is easily removed by the injection pressure of the packer grout material, so that the fixed band does not hinder the expansion of the packer 4.

  Moreover, since the packer 4 is made into a double bag body, the packer grout material is separately injected into the upper and lower bags, and the lower portion of the packer grout material is solidified during the injection. There is no fear of stopping on the way, and the upper part of the packer 4 is reliably injected. In addition, the bag body may be used as it is as a series of 1 m.

  After the packer 4 is bulged in this manner and brought into close contact with the hole wall of the insertion hole 11, the injection inner tube 2 is slid to place the discharge port 9 between the packers 4 of the injection outer tube 1. The chemical solution is discharged into the hollow tube 3. As shown in FIG. 4, the chemical solution injected into the hollow tube 3 is discharged from the injection port formed here, pushes open the vertical slit 7 a provided in the slit disk 7, and the gap portion of the insertion hole 11. To discharge.

  In this case, since the chemical solution is discharged from the vertical slit 7a, it is injected into the surrounding ground through an opening area larger than that in the case of spot injection from a circular hole or the like. The column penetration source can be increased at intervals (2 to 4 m), and even if the discharge rate is increased and the discharge rate is increased (20 to 30 L / min), the permeation rate per unit area is apparently reduced, and the injection pressure Therefore, it is possible to slowly and firmly infiltrate, and since the discharge direction is the vertical direction, a large vertical columnar improvement body can be surely made at a stretch.

  In addition, if a triple packer type tube is used for the injection inner tube 2, the chemical solution can be injected at two locations between the packers 4 at the same time as shown in FIG. A 2-5 m columnar improvement body can be continuously constructed.

It is a front view of an injection outer tube and an injection inner tube showing an embodiment of a medical fluid injection device of the present invention. It is the front view in which the chemical injection device of the present invention was partially cut away. It is explanatory drawing of the packer which is the principal part of the chemical injection device of this invention. It is a front view which shows the ground reinforcement method using the chemical | medical solution injection device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Injection outer tube 2 Injection inner tube 3 Hollow tube 4 Packer 5 Inlet 6 Sleeve 6a ７ 7 Slit board 7a Slit 9 Discharge port 10 Packer part 11 Insertion hole

Claims (1)

  An injection outer tube comprising a plurality of water-permeable bags that swell larger than the hole diameter at intervals in the axial direction, and an injection inner tube that can be inserted into the injection outer tube. In the chemical injection device that fills the inside of the bag with the solidified material from the bag, inflates the bag body to consolidate the surrounding ground and forms a packer, and injects the solidified material between the packers to inject and solidify a predetermined area. The chemical injection device is characterized in that the injection port provided in the injection outer tube is covered with a sleeve with a hook which becomes an openable / closable check valve opened by injection pressure.

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